"No module named rosbag" error

edit

I'm having this problem come up a lot for people using my ros_readbagfile program, while following my ROS tutorial here: Reading messages from a bag file.

I've documented the solution here: https://stackoverflow.com/questions/5...

See the link above for full details, but the gist of it is this:

TLDR;

Run this:

pip3 install bagpy
# OR, if that ends up failing in the end due to a "Permission denied" error, 
# do this:
sudo pip3 install bagpy

Now this will work in your Python 3 script:

import rosbag

...so long as you have the correct hash-bang at the top of your Python 3 file, such as this one:

#!/usr/bin/env python3

Again, see the Stack Overflow link above for additional details.